An integrated circuit usually has a number of circuit components or devices interconnected together by a bus. The bus often has multiple conductive lines.
Some integrated circuits use only a single bus to transfer data among the devices. In most cases, the single bus may establish only a single transfer path to transfer data between only two devices at any given time. In some of these cases, while the bus is busy transferring data between two devices, other devices may also need to use the bus to transfer data. Since the single bus may establish only a single transfer path between only two devices at a given time, the other devices often need to wait for the bus to finish the current data transfer.
Thus, in some integrated circuits, transferring data among the devices via a single bus may be inefficient.